Pittsburgh, Pennsylvania. References. 1. Brook RH, Ware JE Jr, .... Koscik R, Kosorok M, Farrell P, Collins J, Laxova A, Green C, Zeng L,. Rusakow L, Hardie R, ...
Editorials
insured patients did. As in the RAND HIE, it’s likely that both sets of clinical decisions included a mix of appropriate and inappropriate ones. But it sure seems less likely that lifesustaining treatment was withheld from uninsured patients who had a significant chance of functional long-term survival than it is that life-sustaining treatment was continued in insured patients who did not have such a chance. I am hopeful that the expansion of health insurance made possible by the Affordable Care Act will improve equity, increase access, and reduce preventable morbidity and mortality among the nearly 1.3 million Pennsylvanians currently lacking health insurance. However, I am not convinced that reducing the financial disincentive for tracheostomy and thereby increasing the rate of tracheostomy among the 475 uninsured patients a year who are mechanically ventilated (950/2 ¼ 475) to equal the rate among patients with commercial insurance (475 3 0.22 ¼ 106), so that an additional 65 patients receive tracheostomy per year (106 – (82/2) ¼ 65), is likely to achieve those ends. I hope, instead, that removing financial disincentives for clinical preventive services and chronic disease management will reduce the need for intensive care in the first place, even if the RAND HIE never provided any evidence that it would.
751 Author Disclosure: The author does not have a financial relationship with a commercial entity that has an interest in the subject of this manuscript.
Amber E. Barnato, M.D., M.P.H., M.S. University of Pittsburgh Pittsburgh, Pennsylvania References 1. Brook RH, Ware JE Jr, Rogers WH, Keeler EB, Davies AR, Donald CA, Goldberg GA, Lohr KN, Masthay PC, Newhouse JP. Does free care improve adults’ health? Results from a randomized controlled trial. N Engl J Med 1983;309:1426–1434. 2. Siu AL, Sonnenberg FA, Manning WG, Goldberg GA, Bloomfield ES, Newhouse JP, Brook RH. Inappropriate use of hospitals in a randomized trial of health insurance plans. N Engl J Med 1986;315:1259–1266. 3. Fowler RA, Noyahr L, Thornton JD, Pinto R, Kahn JM, Adhikari NKJ, Dodek PM, Khan NA, Kalb T, Hill A, et al. An official American Thoracic Society systematic review: the association between health insurance status and access, care delivery, and outcomes for patients who are critically ill. Am J Respir Crit Care Med 2010;181:1003–1011. 4. Lyon SM, Benson NB, Cooke CR, Iwashyna TJ, Ratcliffe SJ, Kahn JM. The effect of insurance status on mortality and procedure use in critically ill patients. Am J Respir Crit Care Med 2011;184:809–815.
DOI: 10.1164/rccm.201107-1347ED
The Importance of Imaging in Cystic Fibrosis Cystic fibrosis (CF) clinicians need better ways of assessing lung disease, including modalities that can better predict children at risk for poor pulmonary outcomes, the leading cause of morbidity and mortality in CF. Encouragingly, interdisciplinary CF care teams and innovative therapies over the last two decades have resulted in healthier children and teenagers with milder lung disease as evaluated by lung function testing (1). However, spirometry may be limited in evaluating mild pulmonary disease, particularly because bronchiectasis appears to occur early in life and can be relatively focal in nature (2). Plain chest radiographs and scoring systems have been used to evaluate disease progression for 40 years (3–5), and the advent of multi-detector chest CT scan technology has given clinicians a more precise mode for imaging CF lung damage. The question remains, however, whether chest radiology, and specifically scored CT scans, is predictive of future clinical outcomes. Previous retrospective studies in CF would suggest not (6), but a recent prospective study by Loeve and coworkers has demonstrated that CT scans can predict future pulmonary exacerbation (7). In this issue of the Journal, Sanders and colleagues (pp. 816) (8) used data from the Wisconsin Cystic Fibrosis Neonatal Screening Project (WI RCT) (9) to assess the utility of plain chest radiographs and chest CT scans in predicting future pulmonary disease. Starting with a scoring system by Bhalla and coworkers (10), chest CT scans have been used in CF to quantify structural damage, including bronchiectasis, for over 20 years. Brody and colleagues revised this scoring system to better reflect the types and distribution of damage seen in the lungs of patients with CF (11, 12). In this study by Sanders and colleagues, children involved in the WI RCT underwent baseline chest radiographs and CT scans. Measures of pulmonary status such as respiratory microbiology, spirometry, and chest radiograph scores were then gathered prospectively. Sanders and coworkers used linear regression to determine associations between Brody CT scores at baseline and the most recent measures of lung function. The associations were also analyzed using multivariate regression to control for baseline factors that are known
predictors of pulmonary outcomes in CF. The analyses were then repeated for the bronchiectasis subset score of the Brody CT score at baseline. For the first time, this study was able to show a significant association between the severity of lung disease on CT scan and subsequent measures of lung disease obtained on average 7.5 years later, including both lung function measures and chest radiograph scores. Interestingly, the Brody bronchiectasis subset score showed even stronger associations than the overall Brody score. A key strength of this study is its longitudinal nature. No other study has prospectively gathered a comprehensive data set over such an extended period of time and correlated it with baseline chest CT scans. Although baseline spirometry was associated with later outcomes, CT scores were more closely related to long-term outcomes than were either FEV1 % predicted or FEF25–75 % predicted. Further strengthening these findings is the fact that multivariate analysis adjusting for baseline confounding factors did not change the associations found. One compelling finding in the study by Sanders and colleagues is that the Brasfield and Wisconsin chest radiograph scores (5, 13) obtained at the time of the baseline CT scan proved to be excellent predictors of future lung dysfunction and were not outperformed by the CT scores. This makes sense, as bronchiectasis is a significant factor in these radiograph scoring systems and was independently associated, per the Brody score subsets, with future lung disease. Patients with CF experience extensive radiation exposure in their lifetime, especially as they are living longer. Simple chest radiographs that are rigorously scored may be more than adequate predictors of future lung dysfunction, and used in place of chest CT scans, would reduce radiation exposure. Despite the findings published in the study by Loeve and coworkers about CF pulmonary exacerbations (5), Sanders and colleagues were unable to confirm a correlation between baseline CT scores and future pulmonary exacerbations. This is likely because the population in the study by Sanders and coworkers was young and healthy and had very few exacerbations during
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the study period. Nonetheless, taken together, these two studies provide compelling evidence that CT scan scores are good predictors of future lung dysfunction. It would have been interesting to know if higher baseline CT scores were predictive of an accelerated rate of FEV1 decline from baseline to follow-up spirometry using longitudinal modeling; however, this study may not have been powered to evaluate this highly variable outcome. It is important to realize that further studies will be needed to determine whether or not specific findings in chest radiographs or CT scans will be able to directly predict outcomes in a given patient. Overall this study is novel in its confirmation for the CF community that CT scans and plain chest radiographs have a role in predicting future lung disease and may be useful in identifying children at risk for worse pulmonary outcomes. The optimal timing of scored radiography to predict outcomes is unknown. The average age at baseline chest radiograph and CT scan was 11.5 years in Sanders’ observation, and generally the radiography scores, both on CT scan and on chest radiograph, showed mild structural lung disease. Earlier imaging might allow earlier intervention for children at risk (2), but could be too early to pick up the magnitude of structural change seen in this study. More research is needed and the Cystic Fibrosis Foundation’s registry (1) could be an important tool for correlating radiology with future lung dysfunction in a large cohort. CFF guidelines currently recommend obtaining yearly chest radiographs (14, 15). However, these radiographs need to be scored by trained radiologists using standardized scoring systems (5, 13) to be of greatest use in epidemiologic analyses. If standardized scores were reported with yearly CF patient data to the registry in a more consistent manner, then comprehensive longitudinal analyses could be accomplished. Chest CT scans may have a role the routine monitoring of children with CF; however, radiation exposure must be minimized, particularly if repeated scans are to be obtained over the life span. More importantly, it appears that plain chest radiographs with rigorously applied scoring systems may be as effective in predicting lung disease progression and would accomplish this goal with less radiation exposure and at lower cost. Author Disclosure: Neither author has a financial relationship with a commercial entity that has an interest in the subject of this manuscript.
Cori Daines, M.D. Wayne Morgan, Department of Pediatrics University of Arizona Tucson, Arizona
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2011
References 1. Cystic Fibrosis Foundation Patient Registry. 2009 Annual Data Report. Bethesda, MD: Cystic Fibrosis Foundation; 2011. 2. Stick SM, Brennan S, Murray C, Douglas T, von Ungern-Sternberg BS, Garratt LW, Gangell CL, De Klerk N, Linnane B, Ranganathan S, et al.; Australian Respiratory Early Surveillance Team for Cystic Fibrosis (AREST CF). Bronchiectasis in infants and preschool children diagnosed with cystic fibrosis after newborn screening. J Peds. 2009; 155:623–628. 3. Reilly BJ, Featherby EA, Weng TR, Crozier DN, Duic A, Levison H. The correlation of radiological changes with pulmonary function in cystic fibrosis. Radiology 1971;98:281–285. 4. Chrispin AR, Norman AP. The systematic evaluation of the chest radiograph in cystic fibrosis. Pediatr Radiol 1974;2:101–106. 5. Brasfield D, Hicks G, Soong S, Tiller RE. The chest roentgenogram in cystic fibrosis: a new scoring system. Pediatrics 1979;63:24–29. 6. Cademartiri F, Luccichenti G, Palumbo AA, Maffei E, Pisi G, Zompatori M, Krestin GP. Predictive value of chest CT in patients with cystic fibrosis: a single-center 10-year experience. AJR Am J Roentgenol 2008;190:1475–1480. 7. Loeve M, Gerbrands K, Hop WC, Rosenfeld M, Hartmann IC, Tiddens HA. Bronchiectasis and pulmonary exacerbations in children and young adults with cystic fibrosis. Chest 2011;140:178–185. 8. Sanders DB, Li Z, Brody AS, Farrell PM. Chest CT scores of severity are associated with future lung disease progression in children with CF. Am J Respir Crit Care Med 2011;183:816–821. 9. Farrell PM. Improving the health of patients with cystic fibrosis through newborn screening. Wisconsin cystic fibrosis neonatal screening study group. Adv Pediatr 2000;47:79–115. 10. Bhalla M, Turcios N, Aponte V, Jenkins M, Leitman BS, McCauley DI, Naidich DP. Cystic Fibrosis: scoring system with thin-section CT. Radiology 1991;179:783–788. 11. Brody AS, Klein JS, Molina PL, Quan J, Bean JA, Wilmott RW. Highresolution computed tomography in young patients with cystic fibrosis: Distribution of abnormalities and correlation with pulmonary function tests. J Pediatr 2004;145:32–38. 12. Brody AS, Kosorok MR, Li Z, Broderick LS, Foster JL, Laxova A, Bandla H, Farrell PM. Reproducibility of a scoring system for computed tomography scanning in cystic fibrosis. J Thorac Imaging 2006; 21:14–21. 13. Koscik R, Kosorok M, Farrell P, Collins J, Laxova A, Green C, Zeng L, Rusakow L, Hardie R, Campbell P, et al. Wisconsin cystic fibrosis chest radiograph scoring system: validation and standardization for application to longitudinal studies. Pediatr Pulmonol 2000;29:457– 467. 14. Davis PB, Drumm M, Konstan MW. Cystic fibrosis. Am J Respir Crit Care Med 1996;154:1229–1256. 15. Ramsey BW. Management of pulmonary disease in patients with cystic fibrosis. N Engl J Med 1996;335:179–188.
DOI: 10.1164/rccm.201108-1435ED
Psychological Stress: A Social Pollutant That May Enhance Environmental Risk Evidence suggests an etiologic role for both physical toxins (1) and social determinants (2, 3) in the evolution and trajectory of children’s lung function growth and development. Traffic-related air pollution is a global public health problem (4), and children may be most vulnerable (5). The adverse effects of air pollution on respiratory development in children have been extensively documented (6). In parallel, a growing body of literature
Supported by R01 HL080674-06.
suggests that psychological factors influence the programming of neuroendocrine, autonomic, and immune inflammatory processes implicated in respiratory development, suggesting they too play a role in lung development, although studies in humans remain scarce (2, 7). Whereas traditional research has focused on the main effects of social and physical environmental factors, evolving research underscores the importance of interactions among these factors (8). Although a number of theoretical models have been put forth to explain how social conditions “get into the body” to
